Christopher A. Hansen is an American civil rights attorney, notable for litigating many cases while at the ACLU, including the AMP v. Myriad Genetics (2013) case at the US Supreme Court and the ACLU's efforts in ACLU v. Reno (1997). Hansen was at the ACLU for 40 years, from 1973 to 2013, retiring as Senior National Staff Counsel, and the ACLU's longest-serving attorney. Hansen attended Carleton College and earned a law degree from the University of Chicago. He joined the ACLU in 1973, working with its new-found Mental Health Law Project.